Method of building construction



Sept. 11, 1962 G. T. GRAHAM 3,053,015

METHOD OF BUILDING CONSTRUCTION Filed June 26, 1959 3 Sheets-Sheet 1 INVENTOR ATTORNEYS Se t. 11, 1962 G. 'r. GRAHAM METHOD OF BUILDING CONSTRUCTION 3 Sheets-Sheet 2 Filed June 26, 1959 INVENTOR ATTORNEY) p 11, 1962 G. T. GRAHAM 3,053,015

METHOD OF BUILDING CONSTRUCTION Filed June 26, 1959 3 Sheets-Sheet 3 Ti? I @h a y A INVENTOR ATTORNEYS Ail i Patented Sept. 11, 1962 3,653,915 METHGD OF BUILDING CONSTRUCTION George T. Graham, V.P.I. Station Box 3831, Blackshurg, Va. Filed June 26, 1959, Ser. No. 823,146 Claims. (Cl. 50-534) This invention relates to methods for building construction and more particularly to building construction of the type in which concrete slabs are poured or formed on the ground and are raised into position on the supporting columns.

Priorly, numerous difierent methods have been employed to construct buildings in which slabs of concrete were formed on the ground and are raised on supporting columns to their appropriate position on the columns to define a series of floors. The present methods employ the use of a stacked series of columns if the height of the building is to exceed a predetermined figure, for example, 35 feet.

It is current practice to employ a first set of columns approximately 35 feet in height to pour the concrete slabs on the ground and to raise them to the top of these columns by means of jacks mounted on the tops of the columns. The next steps in this mode of construction are to remove the jacks from the tops of the columns and individually raise a second group of columns into abutting relationship with the tops of the first set of columns. The next steps are to mount the jacks on the tops of the second set of columns, raise predetermined ones of the slabs from the first set of columns until they reach the top of the second set of columns and remove the jacks from the tops of the second set of columns. Subsequent steps are individually raising and splicing a third set of columns onto the second set of columns, mounting the jacks on the tops of the third set of columns and raising certain of the slabs from the second set of columns to the third set of columns so that all of the floors are in their final positions. In this method of construction guy wires are connected to the columns and to ground during the lifting operation or braces are conneoted between the columns. A more detailed description of this method of construction is set forth in the Journal of American Concrete Institute, vol. 29, No. 7, pp. 579-589, January 1958, entitled Multi-Story Lift- Slab Construction by W. Sefton.

It will be apparent in view of the large number of steps involved that the method is both timeand labor-consuming. It is further apparent that a crane is require to lift the second and third sets of columns into position. A crane is a very expensive item in the cost of this method of building construction.

Accordingly, it is an object of this invention to provide an improved method of constructing buildings of the type in which slabs are lifted from the ground to their ultimate positions on the columns.

It is a further object of this invention to provide an improved method for constructing a building which is cheaper and faster than the methods described above".

It is a further object of this invention to provide an improved method of constructing buildings of the above mentioned type in which the jacks are employed to raise the columns as well as the slabs.

Briefly, in accordance with aspects of this invention, telescoping columns are employed in this type of building construction. The slabs are lifted by jacks mounted on top of the columns and connected to the slabs by lift rods. Advantageously, the jacks and lift rods are also employed to lift the inner column sections. In one illustrative example of this invention, one group of the slabs is raised to the top of the telescoped column sections by means of jacks mounted on the third column section of each telescoped column. Throughout the specification, the columns will be explained as having three telescoping sections. It is to be understood, however, that any number of sections may be employed. The slabs are connected to the jacks by means of lift rods. When these lift rods are in an elevated position, the second and third column sections are lifted on the lift rods by rotating threaded nuts which encircle the lift rods and co-operate with a collar connected to the innermost column section. In the first step of raising the column sections on the lift rods, the third column section is keyed to the second column section so that the second column section is raised with the third column section. When the column sections have been raised to the point at which the second column section is in its final position, a pin is driven through a suitable hole in the first column section beneath the second column section to secure the second column section in position. The first column section is then welded to the second column section further to secure the second column section in position.

Subsequent to this securing step, certain of the slabs are lifted into position at the top of the second column sec tion, while certain other of the slabs are raised to their final positions along the second column section.

The lift rods are now secured to the lowermost slab at the top of the second column section. The pin through second and third column sections is removed and the jack is driven to lift the collar up the lift rods in the manner previously described so that the third column section is raised to its final position. The column section is now pinned and Welded in position so that the columns extend to the ultimate height of the building and the final slabs are raised to their final positions. As each slab is raised into its final position, it is keyed to the appropriate column or secured by a shear plate. The key or plate is welded or otherwise secured to the column and the lift rods are removed. When all of the columns are in their fully extended position, and all of the slabs are raised to their final position, the jacks may be removed from the third column sections.

In accordance with other aspects of this invention, the lift slab collars are provided with ball sockets and the lift rod-s have a ball on one end. When the lift rod ball is engaged with the collar ball socket, either a tensile or a compressive stress may be applied to the lift rod by the jack. The jacks first apply a tensile stress to the rods to raise one or more slabs to a predetermined position. When the slabs reach this position, they are pinned to the columns and the jacks are employed to apply a compressive stress to the rods to raise the inner telescoping column sections to an elevated or extended position.

In accordance with other aspects of this invention, a number of split guide collars are employed to engage the columns and the lift rods. The guide collars are secured to the columns but slid-ably engage the lift rods so that these collars prevent buckling of the lift rods while the columns are being raised on the lift rods. After the columns are in a fully extended position, the guidecollars are removed to permit the slabs to be raised to their positions. Similarly, split nuts are employed in conjunction with the jack and the collars secured between the innermost column and the lift rods so that the nuts may be removed and attached to the lift rods at any point intermediate the ends of the lift rods.

The advantage in the above described method will be immediately apparent. For example, no crane will be required to place the sections of the support columns since the raising of the inner column sections is achieved by means of the lift rods. Another distinct advantage of this invention is that of obviating the necessity for removing and rep-lacing each jack a number of times before the ultimate column height is achieved. The jack is secured to the third, or innermost, of the telescoping columns only once when the telescope/d column is initially placed in position and removed only once when the telescoping column has been extended to its entire length.

Accordingly, it is a feature of this invention to provide an improved method for building construction by utilizing telescoping columns and a jack mounted on the innermost section of each telescoping column, which jack is employed both to lift the slabs into position and to raise the sections of the column to their final positions.

It is another feature of this invention to employ a method of building construction in which a number of guide sleeves are secured to the column and slidably engage the lift rods to prevent buckling of the lift rods while the lift rods are subject to the compressive stress resulting from the lifting of the inner sections of the column.

It is another feature of this invention to employ the steps of keying sections of a telescoping column together during the course of building construction and raising these keyed sections as a unit by driving the collars connected to one of these sections up the lift rods.

It is another feature of this invention to employ collars and lift rods in combination with a concrete slab, which collars and lift rods are disengageably connected in a manner such that both compressive and tensile forces may be exerted on the lift rod collar connection.

These and various other objects and features of this invention will be more clearly understood from a detailed reading of the specification in conjunction with the drawings, in which:

FIGURE 1 is a schematic representation of a view in elevation, partially in section, of structure employed to perform my method of building construction;

FIGURES 2, 3, 4 and 5 are schematic views, to a reduced scale, of structure of FIGURE 1 showing the result of the movement accomplished during the steps of method;

FIGURES 6 and 7 are plan and elevation views, respectively, of the lifting collars employed in the accomplishment of this method :of building construction; and

FIGURE 8 is a view, to an enlarged scale, of one of the guide collars or yokes employed in this method of building construction taken along the lines 8-8 of FIG- URE 3.

FIGURES 9A and 9B are sectional views in elevation and plan, respectively, of a pontion of the column sections according to this invention.

Referring now to the drawing, FIGURE 1 is a view in elevation, partly in section, of the building during the initial stages of construction, depicting telescoping columns 10 such as may be employed to accomplish the novel method of this invention. The columns 10 are bolted on a suitable base 12 by any well known means, such as anchor bolts 11 embedded in the foundation 12, and extending through the bases 14 of the column-s 10. The foundation 12 may, advantageously, be poured concrete. In this particular example, the columns 10 comprise three telescoping sections 16, 18 and 20. These telescoping sections are employed to raise and support the slabs 22 through 32 which are to the employed as the floors of the finished building. As shown in FIGURE 1, the slabs 2232 have been poured on top of each other and on top of the foundation 12 ina manner well known in the art. These slabs are formed of concrete and horizontal support rods (not shown) may be prestressed before the slabs are raised from the stack or pile.

on 'top of section 20 of each column 10 a hydraulic or other suitable jack 37 is secured by suitable means such as by bolts. A pair of lift rods 38 are employed to conmeet the slabs 2232 wit-h each of the jacks 37 and the link between each pair of the lift rods 38 and the jack 37 is provided by means of jack collars 40 and 41, which are secured to the top and bottom of the jacks 37, respectively. A pair of nuts 42 which may, advantageously, be of the split or hinged type, encircle the rods 38 above the jack collar 40 to prevent the jack collar 40 from sliding up the lift rods 38. Nuts 43 and 44 cooperate in a similar manner with collar 41. Nuts 42, 43 and 44 may be selectively rotated by means of a sprocket and chain drive (not shown) driven by the hydraulic jack motor, which structure is all well known in the field of building construction of the type in which slabs are formed on the foundation and lifted into place.

When the hydraulic jack 37 is driven by means of fiuid delivered through suitable hoses (not shown), the jack eifectively expands between the section 20 of the column 10 and jack collar 44). This expansion of the jack, which may have a relatively short stroke, such as a matter of a few inches, lifts the jack collar 40, the lift rods 38 and the slab or slabs through the distance equal to this stroke.

Advantageously, the lower ends of the rods 38 are in the form of ball joints 45. Also, advantageously, a metal lift collar 46 is a cast in each slab where it encircles the column 10 and these collars 46 have ball sockets 47 to receive the ball joints 45. These ball joints may be selectively engaged in and disengaged from ball sockets 47 in the lift collars 46. For example, these ball joints may first be engaged with lift collar 46 of slab 22 which is the slab abutting the foundation 12. Accordingly, any lift exerted by the jack 37 will lift all of the slabs. During the lifting operation, guy wires need not be employed to equalize any lateral forces which may be developed since these forces are balanced by the columns. Advantageously, these columns are provided with sections which overlap each other to resist any lateral forces which might develop due to wind or the slabs. These overlap sections will be subsequently described.

The first step in the operation of lifting the slabs into place is that of lifting several of the slabs a few inches by means of the extension or expansion stroke or jack 37. During this first step, nuts 42 are stationary and nuts 43 and 44 rotate in a clockwise direction (as viewed from the tops of rods 38) to permit rods 38 to slide through lift-yoke 41. For the second step, the jacks 37 are reversedly driven or contracted while the nuts 42 are rotatably driven in a clockwise direction to move downwardly on the lift rods 38. Nuts 43 and 44 are maintained stationary during this second step.

These individual strokes and retractions of the jack 37 are continued until the lowest slab, namely, slab 22, has reached its final position, as shown in dotted lines in FIG- URE 1 and in solid lines in FIGURE 2. Then the slab 22 is secured in position by a seat plate 48, the ball joints 45 of the lift rods 38 are disengaged from the lift collars 46 of slab 22 and these ball joints 45 are then engaged with the lift collars 46 of the slab 23. The lifting process is continued according to steps one and two until the slab 23 has reached its final position, as shown in FIG- URE 2. When slab 23 has reached its final position and is keyed or otherwise secured in place, the ball joints 45 or rods 38 are disengaged from the lift collars 46 of slab 23 and are engaged with the lift collars 46 of slab 24. At this point, it is necessary to increase the column height to provide column length on which the parked slabs 25-32 may be lifted and to provide room for the movement of slab 24 into its final position. This is done by extending the telescoping sections 18 and 20 of the colurnns 10.

Advantageously, the lifting of the column sections 18 and 20 may be accomplished through the operation of the jack 37 and the co-operation of lift-yoke 41 and the nuts 43 and 44. The nuts 43 and 44 have sprockets (not shown) thereon and these sprockets are driven by means of the hydraulic jack motor previously mentioned. When these nuts 43 and 44 are rotated on the threads of lifting rods 38, the nuts 43 and 44 lift against the lift yokes 40 and 41, respectively, to lift the inner sections 18 and 20 of the column 10. It is, of course, understood that at the same time the nuts 43 and 44 are being rotated, the nuts 42 are being rotated so that the yoke 40 may move upwardly on the rods 38.

Since the lift rods 38 are now receiving a compressive stress, they may be linked intermediate their ends to the outer section 16 of the columns by means of suitable guide yokes 50, shown in FIGURES 3 and 8, which will be subsequently explained in detail. The rotation of the nuts 42, 43 and 44 continues until the second section 18 and the third section 20, which are advantageously keyed together, are lifted to a position such that section 18 is extended to its final position, as shown in FIGURE 4. When the section 18 is in its final position, a suitable key, such as key 53, is driven through suitable holes in the section 16 to define a support for the bottom of section 18. As an additional support, the sections 16 and 18 may be welded together, as shown generally at 55.

The lower portions of the ball sockets 47 have lips or flanges which partially encircle the balls 45. These flanges prevent the balls 45 from slipping out of the sockets 47. Split nuts such as nuts 51, shown in FIGURE 3, may also be employed to balance this compressive stress.

Slabs 25 through 32 may now be lifted and parked (locked in position or keyed to the section 18) as shown in FIGURE 4, in a manner previously described. The lift rods 38 may then be disengaged from the slab 25 through the action of the ball joints 45 and the collars 46 and these lift rods 38 may then be employed to lift the slabs 26' through 32 until slab 26 is keyed in its final position. Slabs 27 through 32 are then lifted to a position, shown in FIGURE 5, in which slab 27 is shown in solid lines and slabs 2832 are shown in dotted lines.

Sections 18 and 20 have been keyed together throughout this series of steps by means of keys, such as 57 and 59, shown in FIGURES 6 and 7. Lift rods 38 are dis engaged from slab 27 and engaged in the collars 46 of slab 28 to define a new base for lifting column sections 20. Keys 57 and 59 are now removed and the section 29 is elevated through the action of nuts 43 and 44 acting on lift yokes 4i) and 41 in a manner previously described, until the sections 20 are raised to their ultimate position, as shown in FIGURE 5. During this column lifting operation, guide yokes 50 are again employed to prevent buckling of the rods 38 under the compressive stress of the weight of the sections 20. When the sections 20 are in their final position, suitable pins, such as pins 68, are driven through the section 18 to define a base for the sections 20.

The remaining slabs 28 through 32 are now raised to their final positions in the manner previously described with respect the other slabs and these slabs are locked into position by suitable collars welded to the column sections 20. The lifting operation is now completed and the lifting rods 38 and the jack 37 may be removed.

From the foregoing explanation, the novel and useful aspects of this method of construction will be apparent. Throughout this method it has been necessary to install and remove the jacks 37 only once. Further, by walking the column sections up the lift rods 38, the use of a crane has been obviated. Still further, by employing telescoping columns, the time and labor required has been appreciably diminished.

The lifting collars 46 are shown in detail to an enlarged scale in FIGURES 6 and 7. As therein depicted, the collars 46 have a ball socket 47 therein so that both compressive and tensile stresses may be applied to the lift collar 46 through the lift rods 38 in a manner previously described. The ball joint 45 may readily be removed from the ball socket 47 by the release of all stress upon the rod 38 and the movement of the ball joint 45 in a direciton perpendicular to the axis of the collar 46.

One of the guide yokes or guide collars employed during the column section lifting operation, in which the lift rods are under compressive stress, is best seen in FIG URE 8. As therein depicted, the guide collar or guide yoke 50 is hinged, such as shown at 65, and these guide collars have securing means 67 at the side opposite the hinge. The guide yoke 50 has a first aperture 68 therein and may, advantageously, have teeth 70 defining aperture 68 for the purpose of snugly engaging the sections such as 16 and 18 of the column 10. Apertures 71 and 72 are provided in the guide yoke 50 and these apertures are sutficient to permit the passage of thelift rods 38 therethrough. Advantageously, these apertures 71 and 72 may have bearing surfaces which engage the rods 38 when the rods 38 are compressed to the point of forcing against the guide yokes 50. It is, of course, understood that if the guide rods 38 are sufficiently large and the sections 18 and 20 of the columns 10 are relatively light, then the need for guide collars 50 will be obviated. However, in the interest of employing the smallest size lift rods 38, which are economically and physically feasible, the guide collars should be installed during the lifting operation of the sections 18 and 20. These guide yokes will be removed subsequent to each of the lifting operations of the column sections 18 and 20 to permit the free passage of the slabs 25 through 32 along the sections of the columns 10.

As a further step in stabilizing the entire structure during the lifting operation, split sleeves, such as 75 and 80, may be employed to fill the spaces between slabs 25 through 32 and sections 18 and 20 of the columns 10. The sections 18 and 20 are of progressively smaller outer diameter than the inner diameter of lift collars 46 and the slabs 25 through 32 should securely engage sections 18 and 20. For example, the outer diameters of sections 16, 18 and '20 may be 12'', l0" and 8", respectively.

Referring now to FIGURES 9A and 9B, there is depicted section views in elevation and plan, respectively, of one of the overlapping sections of the columns 10. A pin is driven through suitable holes 91 and 92 in the section 16 to define a temporary vertical support for section 18. Eight guy bolts, such as bolts 93, 94, 95 and 96, are positioned in section 16, four in each of two planes. Advantageously, these guy bolts are selectively rotated to bring the section 18 into plumb. Further, these bolts balance any lateral forces applied to the sections such as 18 and 20.

While I have shown and described various embodiments of my invention, it is understood that the principles thereof may be extended to many and varied types of apparatus. The invention, therefore, is not to be limited to the details illustrated and described herein.

What is claimed is:

1. A method of building construction comprising the steps of mounting a plurality of telescoping columns on a foundation, each column including a plurality of concentric sections, connecting the inner sections together, securing jacks to the top of the innermost section of each of the telescoping columns, slidably mounting a plurality of lift collars around the outer section of the telescoping columns, forming a plurality of slabs on said foundation, each of said slabs containing one of the lift collars on each of the columns, connecting each of the jacks to one of the slabs by means of lift rods, operating the jacks to lift the slabs by lifting the lift rods, locking the lifted slabs in position on the outermost section of the telescoping column and driving the jack up the lift rods to thereby lift the inner sections of said columns.

2. The method of building construction according to claim 1 in which the step of lifting the columns on the lift rods is accomplished by driving a nut on the lower side of a lift yoke up the lift rods, which lift yoke is connected to the jack.

3. The method according to claim 2 further including the step of disconnecting the intermediate column sections from the innermost column section when the intermediate column sections have been raised to their final position to further extend the columns.

4. A method for building construction comprising the steps of mounting a plurality of telescoping columns on a foundation, each of said columns including a plurality of concentric sections, connecting the inner sections of each column together, positioning a number of lift collars around each of said columns, forming a number of parallel slabs on said foundation, each slab containing one of the lift collars on each of said columns, securing a jack on the innermost section of each of said columns, connecting each of said jacks to the lift collar by means of lift rods associated with one of said slabs, actuating said jacks to elevate said slab to a predetermined position, locking said lifted slab in position to define an elevated base, driving said jacks upwardly on said lift rods to elevate the inner sections of said telescoping column upwardly on said lift rods, seeming the outermost section of the telescoping columns to an inner section of said telescoping columns and elevating said lifted slab by actuating said jacks to lift said lift rods.

5. A method for building construction comprising the steps of vertically positioning a number of telescoping columns having at least an outer, an inner and an intermediate section, connecting the inner and intermediate sections together, mounting a plurality of lift collars in sliding relationship on the outer section of said columns, securing a jack on the inner section of each of said columns, connecting each of said jacks to one of the lift collars associated with their respective columns, forming a plurality of slabs each including one of the lift collars on each of said columns, lifting said lift rods by means of said jacks to raise one of said slabs, securing said one slab in its elevated position and driving said jacks upwardly on said lift rods to thereby raise the inner and intermediate sections of said telescoping columns.

6. The method according to claim further including the steps of disconnecting the connection between the inner and the intermediate sections of said columns after said intermediate sections have been secured to said outer section and again repeating the previous steps of elevating one of the slabs, securing the elevated slab in position and driving the jacks upwardly on the lift rods to elevate the inner sections of each of said columns.

7. The method according to claim 6 further including the steps of securing the inner section of said columns to said intermediate section of said column and actuating said jacks to lift said lift rods thereby elevating said slabs.

8. The method according to claim 7 wherein each of said lift collars comprises a plurality of ball joints and each of said lift rods having a ball on one end thereof, the connection and disconnection between the lift collars being accomplished by selective engagement and disengagement of the balls and sockets.

9. The method according to claim 6 further comprising the steps of securing a guide collar to one of the sections of each of said columns while said jacks are being driven upwardly on said lift rods whereby buckling of the lift rods is prevented during the application of compressive stress to the lift rods.

1-0. The method according to claim 6 further comprising the steps of selectively adjusting guy bolts in the overlapping sections of the column to balance lateral forces imparted to the column sections.

References Cited in the file of this patent UNITED STATES PATENTS 2,867,111 Youtz Jan. 6, 1959- FOREIGN PATENTS 684,089 France Mar. 11, 1930 1,109,975 France Oct. 5, 1955 OTHER REFERENCES Lift-slabs Hit Record Height, Engineering News-Record, April 28, 1955, pages 24 and 25.

Lift Slab Method Makes it Debut, Construction News Bulletin, Sept. 19, 1953, pages 4-9. 

